+ Reply to Thread
Results 1 to 4 of 4

Thread: 3 Coin Bet

  1. #1
    Points: 4,755, Level: 44
    Level completed: 3%, Points required for next Level: 195

    Posts
    4
    Thanks
    0
    Thanked 0 Times in 0 Posts

    3 Coin Bet




    Please help me with this problem
    A man has 3 coins as followings:
    Coin 1: Head Head
    Coin 2: Tail Tail
    Coin 3: Head Tail
    He selects one coin, it is a head.
    He bets it is a two-head coin.
    Probability in this case?
    Please help me,
    Thank you in advance.

  2. #2
    TS Contributor
    Points: 13,042, Level: 74
    Level completed: 48%, Points required for next Level: 208
    JohnM's Avatar
    Posts
    1,948
    Thanks
    0
    Thanked 5 Times in 4 Posts
    Using the classical definition of probability, it is:

    probability of an event =
    # ways the event of interest can occur / # possible events

    ...and this is a situation of conditional probability, since we are given that it is a head.

    The probability that the coin is a two-headed coin is 0.5, since there are two coins that can produce a head (we are given the information that it is a head), but only 1 of the 2 is a two-headed coin.

    P(2-headed | head) = 1/2

  3. #3
    Points: 4,755, Level: 44
    Level completed: 3%, Points required for next Level: 195

    Posts
    4
    Thanks
    0
    Thanked 0 Times in 0 Posts
    Thank you very much, Mod
    However, I have another question.
    Would I take the bet that it is a 2-headed coin? For sure????
    Thanks a lot.

  4. #4
    TS Contributor
    Points: 13,042, Level: 74
    Level completed: 48%, Points required for next Level: 208
    JohnM's Avatar
    Posts
    1,948
    Thanks
    0
    Thanked 5 Times in 4 Posts

    There's a 50% chance of winning, so in the long run, you'll break even.

+ Reply to Thread

           




Similar Threads

  1. even and odd probability of coin
    By zhenyazh in forum Probability
    Replies: 1
    Last Post: 01-24-2010, 08:02 AM
  2. Coin flipping
    By StatsH in forum Probability
    Replies: 1
    Last Post: 06-02-2008, 04:11 AM
  3. Tossing a coin
    By smilejoy in forum Statistics
    Replies: 0
    Last Post: 03-28-2008, 11:10 AM
  4. Tossing a coin
    By Protein in forum Probability
    Replies: 5
    Last Post: 02-17-2008, 10:50 AM
  5. Coin A Coin B
    By Whitney in forum Probability
    Replies: 4
    Last Post: 10-11-2006, 12:11 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts






Advertise on Talk Stats